Institute F-A Forel, University of Geneva, Versoix, Switzerland.
Ecotoxicol Environ Saf. 2012 Apr;78:50-6. doi: 10.1016/j.ecoenv.2011.11.005. Epub 2011 Dec 29.
This study characterized the fecal indicator bacteria (FIB), including Escherichia coli (E. coli) and Enteroccocus (ENT), disseminated over time in the Bay of Vidy, which is the most contaminated area of Lake Geneva. Sediments were collected from a site located at ∼500 m from the present waste water treatment plant (WWTP) outlet pipe, in front of the former WWTP outlet pipe, which was located at only 300 m from the coastal recreational area (before 2001). E. coli and ENT were enumerated in sediment suspension using the membrane filter method. The FIB characterization was performed for human Enterococcus faecalis (E. faecalis) and Enterococcus faecium (E. faecium) and human specific bacteroides by PCR using specific primers and a matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS). Bacterial cultures revealed that maximum values of 35.2 × 10(8) and 6.6 × 10(6)CFU g(-1) dry sediment for E. coli and ENT, respectively, were found in the sediments deposited following eutrophication of Lake Geneva in the 1970s, whereas the WWTP started operating in 1964. The same tendency was observed for the presence of human fecal pollution: the percentage of PCR amplification with primers ESP-1/ESP-2 for E. faecalis and E. faecium indicated that more than 90% of these bacteria were from human origin. Interestingly, the PCR assays for specific-human bacteroides HF183/HF134 were positive for DNA extracted from all isolated strains of sediment surrounding WWPT outlet pipe discharge. The MALDI-TOF MS confirmed the presence of general E. coli and predominance E. faecium in isolated strains. Our results demonstrated that human fecal bacteria highly increased in the sediments contaminated with WWTP effluent following the eutrophication of Lake Geneva. Additionally, other FIB cultivable strains from animals or adapted environmental strains were detected in the sediment of the bay. The approaches used in this research are valuable to assess the temporal distribution and the source of the human fecal pollution in aquatic environments.
本研究描述了随时间在日内瓦湖污染最严重的区域维迪湾扩散的粪便指示菌（FIB），包括大肠杆菌（E. coli）和肠球菌（Enteroccocus，ENT）。沉积物是从一个距离现有污水处理厂（WWTP）出口管道约 500 米的地点采集的，位于前 WWTP 出口管道的前面，该管道距离沿海娱乐区仅 300 米（2001 年之前）。使用膜过滤法在沉积物悬浮液中对大肠杆菌和肠球菌进行计数。通过使用特定引物和基质辅助激光解吸电离飞行时间质谱（MALDI-TOF MS），对人类粪肠球菌（E. faecalis）和粪肠球菌（E. faecium）和人类特异性拟杆菌进行了 FIB 特征分析。细菌培养表明，在 20 世纪 70 年代日内瓦湖富营养化期间沉积的沉积物中，大肠杆菌和肠球菌的最大值分别为 35.2×10(8)和 6.6×10(6)CFU g(-1)干沉积物，而 WWTP 于 1964 年开始运行。同样的趋势也出现在人类粪便污染的存在：用引物 ESP-1/ESP-2 进行 PCR 扩增的 E. faecalis 和 E. faecium 的百分比表明，这些细菌中超过 90%来自人类。有趣的是，针对特定人类拟杆菌 HF183/HF134 的 PCR 检测在 WWPT 出口管排放周围沉积物中提取的 DNA 呈阳性。MALDI-TOF MS 证实了从 WWTP 出口管周围沉积物中分离的菌株中普遍存在大肠杆菌和优势肠球菌。我们的结果表明，在日内瓦湖富营养化后，受 WWTP 废水污染的沉积物中，人类粪便细菌大量增加。此外，在海湾沉积物中还检测到了来自动物的其他可培养 FIB 菌株或适应环境的菌株。本研究中使用的方法对于评估水生环境中人类粪便污染的时间分布和来源是有价值的。
